docs: Add build_docs.sh

docs/build_docs.sh

@@ -0,0 +1,17 @@
+#!/bin/bash
+
+set -xeo pipefail
+
+if [ ! -d "virtualenv" ]
+then
+    virtualenv -p python2.7 virtualenv
+fi
+
+(
+    . virtualenv/bin/activate
+    if [ ! -d "virtualenv/lib/python2.7/site-packages/sphinx" ]
+    then
+        pip install -r requirements.txt
+    fi
+    make html
+)

docs/requirements.txt

@@ -0,0 +1,12 @@
+alabaster==0.7.8
+Babel==2.3.4
+docutils==0.12
+imagesize==0.7.1
+Jinja2==2.8
+MarkupSafe==0.23
+Pygments==2.1.3
+pytz==2016.4
+six==1.10.0
+snowballstemmer==1.2.1
+Sphinx==1.4.4
+sphinx-rtd-theme==0.1.9